Sand Impaction - Horse

See Colic Diagnosis in Horses

Medical Treatment of Colic in Horses

Description

Impaction of the large colon is seen in horses with limited access to drinking water or grazing bare pastures. The sand is not ingested but accumulates within the right dorsal colon, pelvic flexure and transverse colon. Due to its high density, the sand forms a sediment within the colon. This type of colic is particularly common in dry sandy regions of the world and is far less common in the UK and rest of Europe.

Clinical signs

Clinical signs are generally dependent on the site of impaction. Horses affected by a pelvic flexure impaction often present with signs of mild abdominal pain and generally respond well to conservative treatment. Impaction of the transverse colon is often associated with more severe abdominal pain due to the build up of gas in the the colon proximal to the obstruction.

Diagnosis

Affected horses may have a history of living in a sandy environment, grazing in dry weather or a reduction in water intake. Definitive diagnosis is made via rectal palpation or transrectal ultrasonography with identification of sand in the colon. An impaction may also be detected per rectum but in many cases the impacted segment of intestine may be out of reach. Transrectal ultrasonography may assist in identifying the presence of sand. Sand also may be seen in the faeces by mixing faecal material with water in a plastic rectal examination sleeve and allowing the sand to fall to the bottom.

Abdominal radiography may be useful in assessing the volume and location of sand impactions in foals, minature horses and small ponies.

Treatment

Bulk laxatives such as Psyllium are used to assist in the movement of sand. Psyllium is administered directly into the stomach via a nasogastric tube and the sand become incorporated into the laxative. This treament is continued for up to a week until all sand is fully removed from the colon.

If the impaction is large or non-responsive to medical treatment, surgery may be indicated.

Prognosis

For cases that are not resolved by conservative treatment, the prognosis is good if surgery is performed early.

References

Mezerova, J., Kabes, R., Zert, Z., Jahn, P., Hanak, J. (2001) Impaction of right dorsal colon in the horse: report of 32 cases Vet. Med. - Czech, 46(11-12): 293-300